Prophylactic pregabalin to decrease pain during medical abortion: A randomized controlled trial
Awarded 2015
Complex Family Planning Fellowship Research
EmmaKate Friedlander, MD
University of Hawaii at Manoa

Background: Approximately 272,400 women in the United States used mifepristone and misoprostol to terminate a pregnancy in 2014. Women report moderate to severe pain during medical abortion, with maximum pain scores ranging from seven to eight on an 11-point scale, lasting five or more days for a majority of women. Limited data exists regarding the most effective analgesic regimen. Pregabalin is increasingly used as a preoperative medication to decrease acute pain.
Statement of purpose: We sought to evaluate whether prophylactic pregabalin reduces pain experienced with medical abortion.
Methodology: We conducted a randomized, double-blind, placebo-controlled trial of women up to 70 days of gestation initiating a medical abortion with mifepristone and buccal misoprostol. Participants were randomized to take pregabalin 300 mg or a placebo immediately prior to misoprostol. All participants were dispensed ibuprofen and oxycodone with acetaminophen as additional analgesia to take as needed. To assess the primary outcome of maximum pain on an 11-point numerical rating scale, electronic surveys were sent via text message link at six time points over 72 hours. Surveys also included analgesic usage and adverse effects. A sample size of 55 participants in each arm was planned to detect a clinically significant difference in pain score of 1.3 points, accounting for up to 20% dropout.
Findings: From June 2015 to October 2016, 241 women were screened, 110 were randomized, and 107 provided pain scores. Demographic characteristics were similar between groups. The mean maximum pain scores were not different between groups (5 in the pregabalin group and 5.5 in the placebo group; p=0.32). Ibuprofen was used by 73% of the pregabalin group versus 88% of the placebo group (p=0.04). Narcotics were only used by 31% of the pregabalin group versus 50% of the placebo group (p=0.04). Satisfaction scores for the abortion were higher in the pregabalin group (very satisfied: 41% versus 22%; p=0.03), as were satisfaction scores for the analgesic regimen (very satisfied: 47% versus 22%; p=0.006).
Conclusion: Maximum pain scores were not significantly different between the pregabalin and placebo groups, though women who received pregabalin were less likely to require any ibuprofen or narcotic, and were more likely to report higher satisfaction with the analgesic regimen.